JP2022149906A - Vehicle control device - Google Patents

Abstract

To provide a vehicle control device capable of improving fuel consumption performance while suppressing the degradation of drivability.SOLUTION: A control device 30 for controlling a vehicle 1 that is equipped with an engine 11, a motor generator 12, and drive wheels DW driven by the output of at least one of the engine 11 and the motor generator 12, executes cylinder rest bottom assist control that increases motor torque outputted from the motor generator 12 according to an increase in crank end request torque while keeping engine torque outputted from the engine 11 at cylinder rest bottom torque, when a crank end request torque reaches the cylinder rest bottom torque during the cylinder rest operation of the engine 11.SELECTED DRAWING: Figure 4

Description

The present invention relates to a vehicle control device.

2. Description of the Related Art Conventionally, vehicles equipped with internal combustion engines are desired to have improved fuel efficiency. For example, Patent Document 1 describes a hybrid vehicle that includes an internal combustion engine that can be switched (switched) between full-cylinder operation in which all cylinders are operated and cylinder-deactivated operation in which some cylinders are deactivated, and a motor. , the internal combustion engine is stopped when the target torque for the crank end torque, which is the torque at the shaft end of the crankshaft of the power plant torque output from the power plant consisting of the internal combustion engine and the motor, is equal to or less than a predetermined cylinder stop upper limit torque. A technique has been disclosed in which fuel consumption performance is improved by setting the engine to a cylinder operation state.

JP-A-2005-27466

Increasing the chances of operating the internal combustion engine at the fuel economy optimum operating point will improve fuel efficiency. However, if the internal combustion engine is operated at the optimum fuel efficiency operating point and it becomes impossible to secure an appropriate crank end torque according to the running state of the vehicle, hesitation (so-called vehicle sluggishness) occurs and drivability deteriorates. obtain. From the viewpoint of improving the marketability of vehicles, it is desirable to improve fuel efficiency while suppressing deterioration in drivability.

SUMMARY OF THE INVENTION The present invention provides a vehicle control device capable of improving fuel consumption performance while suppressing deterioration of drivability.

The present invention
A vehicle control device for controlling a vehicle including an internal combustion engine, an electric motor, and driving wheels driven by at least one output of the internal combustion engine and the electric motor,
The internal combustion engine is configured to be switchable between full-cylinder operation in which all cylinders are operated and cylinder-deactivated operation in which some cylinders are deactivated,
The vehicle control device includes:
Based on a target torque for a crank end torque, which is torque at the shaft end of the crankshaft of the power plant torque output from the power plant composed of the internal combustion engine and the electric motor, the operating state of the internal combustion engine is changed to full-cylinder operation and It is possible to switch between cylinder deactivation operation and control the output of the internal combustion engine based on the net fuel consumption rate,
When the internal combustion engine is operating with the cylinder not operating, the target torque is set so that the value of the cylinder deactivating net fuel consumption rate, which is the net fuel consumption rate when the internal combustion engine is operating with the cylinder not operating, is the minimum. When the cylinder bottom torque is reached, cylinder deactivation bottom assist increases the motor torque output from the electric motor in accordance with the increase in the target torque while maintaining the engine torque output from the internal combustion engine at the cylinder deactivation bottom torque. Execute control.

ADVANTAGE OF THE INVENTION According to this invention, the vehicle control apparatus which can improve fuel consumption performance can be provided, suppressing the fall of drivability.

It is a figure which shows an example of the vehicle of this embodiment. It is a figure which shows an example of the transmission with which the vehicle of this embodiment is provided. It is a figure which shows an example of the net fuel consumption rate (BSFC) in the vehicle of this embodiment. FIG. 4 is a diagram showing an example of cylinder deactivation bottom assist control executed by the vehicle control device of the present embodiment; FIG. 5 is a diagram showing another example of cylinder deactivation bottom assist control executed by the vehicle control device of the present embodiment;

Hereinafter, one embodiment of the vehicle control device of the present invention will be described in detail with reference to the drawings.

[vehicle]
As shown in FIG. 1, a vehicle 1 of the present embodiment is a so-called hybrid electrical vehicle, and includes an engine 11 that is an example of an internal combustion engine, a motor generator 12 that is an example of an electric motor, and a transmission TM. , driving wheels DW, a battery 20, a power conversion device 21, and a control device 30, which is an example of the vehicle control device of the present invention. In FIG. 1, thick solid lines indicate mechanical connections, double dashed lines indicate electrical wiring, and solid arrows indicate control signals.

The engine 11 is, for example, a so-called cylinder deactivated engine configured to be switchable between full cylinder operation in which all cylinders are activated and cylinder deactivated operation in which some cylinders are deactivated. As an example, the engine 11 is a V-type 6-cylinder engine equipped with a variable valve timing mechanism (not shown), and is configured to be able to deactivate three cylinders of one bank by means of the variable valve timing mechanism. That is, in the engine 11, 6-cylinder operation using 6 cylinders of both banks is performed during full-cylinder operation, and 3-cylinder operation using only 3 cylinders of one bank is performed during cylinder deactivation operation. Further, the engine 11 may be configured to be able to change the valve opening period, opening/closing timing, lift amount, etc. of each intake valve by a variable valve timing mechanism.

The engine 11 outputs mechanical energy (power) generated by burning supplied fuel (eg, gasoline) by rotationally driving a crankshaft 11a (see FIG. 2). Power output from the engine 11 (hereinafter also simply referred to as output of the engine 11) is transmitted to the drive wheels DW via a transmission TM mechanically connected to the engine 11, and is used for the vehicle 1 to run. .

The engine 11 is also mechanically connected to the motor generator 12 . The motor generator 12 is, for example, a three-phase AC motor, and functions as an electric motor that outputs power when electric power is supplied. Specifically, a rotor (not shown) of the motor generator 12 is connected to the crankshaft 11 a of the engine 11 . Therefore, the crank end torque, which is the torque at the shaft end of the crankshaft 11a of the power plant torque output from the power plant composed of the engine 11 and the motor generator 12, is the torque output from the engine 11 (hereinafter also referred to as engine torque). ) and the torque output from the motor generator 12 (hereinafter also referred to as motor torque).

Since the engine 11 and the motor generator 12 are mechanically connected, in the vehicle 1, the driving of the drive wheels DW using the output of the engine 11 (that is, the running of the vehicle 1) is output from the motor generator 12. A motor assist that assists with the power (hereinafter also simply referred to as the output of the motor generator 12) is possible.

Further, since the engine 11 and the motor generator 12 are mechanically connected, the motor generator 12 can be rotationally driven by the output of the engine 11, and the engine 11 can be rotationally driven by the output of the motor generator 12. It is possible. Specifically, in the vehicle 1 , the engine 11 can be started by cranking by the motor generator 12 .

Motor generator 12 is electrically connected to battery 20 via power converter 21 . The battery 20 is, for example, a battery that has a plurality of power storage cells connected in series and is configured to be capable of outputting a predetermined voltage (eg, 50 to 200 [V]). A lithium-ion battery, a nickel-metal hydride battery, or the like can be used as the storage cell of the battery 20 .

The power conversion device 21 is a device that includes an inverter, a DC/DC converter (none of which is shown), and the like, and is controlled by the control device 30 to convert power. For example, the power conversion device 21 converts the DC power supplied from the battery 20 into three-phase AC power and supplies it to the motor generator 12, or converts the three-phase AC power supplied from the motor generator 12 into DC power. It is converted and supplied to the battery 20 . The motor generator 12 is supplied with electric power from the battery 20 via the power conversion device 21, and thus can perform the aforementioned motor assist.

The motor generator 12 also functions as a generator that generates power by being rotationally driven. The motor generator 12 can be driven to rotate by the output of the engine 11 as described above, and can also be driven to rotate by power input from the drive wheel DW side due to braking of the vehicle 1 or the like. Electric power generated by the motor generator 12 is supplied to the battery 20 via the power conversion device 21 and used to charge the battery 20 .

The transmission TM is a multi-stage transmission having a plurality of gear stages (for example, seven stages), and is provided in a power transmission path from the engine 11 to the drive wheels DW. Specifically, the transmission TM includes a torque converter 13 and a gear box 14 as shown in FIG.

The torque converter 13 has a pump impeller 131 , a turbine runner 132 , a stator 133 and a lockup clutch 134 . The pump impeller 131 is mechanically connected to the engine 11 and the motor generator 12 (specifically, the crankshaft 11a) and integrally rotates as they are rotationally driven. The turbine runner 132 has a hydraulic fluid inlet located close to the hydraulic fluid discharge port of the pump impeller 131 , is mechanically coupled to the input shaft 141 of the gearbox 14 , and rotates integrally with the input shaft 141 . Stator 133 is sandwiched between turbine runner 132 and pump impeller 131 to deflect the flow of hydraulic oil from turbine runner 132 back to pump impeller 131 . The stator 133 is also supported by a housing (not shown) of the torque converter 13 or the like via a one-way clutch 135 . The torque converter 13 transmits power (rotational power) from the pump impeller 131 to the turbine runner 132 via the hydraulic oil by circulating the hydraulic oil in a circulation path formed between the pump impeller 131 and the turbine runner 132. can.

The lockup clutch 134 is a clutch that can mechanically connect and disconnect the engine 11 and the input shaft 141 of the gearbox 14 . By engaging the lockup clutch 134 , the output of the engine 11 can be directly transmitted to the input shaft 141 of the gearbox 14 . That is, when the lockup clutch 134 is in the engaged state, the crankshaft 11a of the engine 11 and the input shaft 141 of the gearbox 14 rotate integrally.

The gearbox 14 includes an input shaft 141 to which the output of the engine 11 and the motor generator 12 is transmitted via the torque converter 13, a plurality of transmission mechanisms 142 and 143 capable of changing the speed of the power transmitted to the input shaft 141, and and an output member 144 including an output gear 144a that outputs power shifted by any one of the plurality of transmission mechanisms to the drive wheel DW side.

The plurality of transmission mechanisms included in gearbox 14 include first transmission mechanism 142 and second transmission mechanism 143 . The first transmission mechanism 142 includes a first transmission clutch 142a, a first drive gear 142b that rotates integrally with the input shaft 141 when the first transmission clutch 142a is engaged, and a first driven gear that rotates integrally with the output member 144. 142c. The second transmission mechanism 143 includes a second transmission clutch 143a, a second drive gear 143b that rotates integrally with the input shaft 141 when the second transmission clutch 143a is engaged, and a second driven gear that rotates integrally with the output member 144. 143c.

Although FIG. 2 shows only the first transmission mechanism 142 and the second transmission mechanism 143 as the transmission mechanisms included in the gearbox 14, the gearbox 14 may include the first transmission mechanism 142 and the second transmission mechanism 143, for example. A transmission mechanism (not shown) other than the transmission mechanism 143 is also provided.

Whether each clutch provided in the transmission TM such as the lockup clutch 134, the first shift clutch 142a, and the second shift clutch 143a (hereinafter simply referred to as the clutch of the transmission TM) is in an engaged state or a released state is determined by It is controlled by the controller 30 .

Returning to FIG. 1, the control device 30 is a device that controls the engine 11, the transmission TM, the power conversion device 21, and the like. Furthermore, control device 30 can also control motor generator 12 through control of power conversion device 21 . Further, the control device 30 may directly control the motor generator 12 or may control the input/output of the battery 20 . The control device 30 includes, for example, a processor that performs various calculations, a storage device that stores various information, an input/output device that controls input/output of data between the inside and outside of the control device 30, and the like. Realized.

Various sensors are connected to the control device 30, and the control device 30 controls the engine 11, the transmission TM, the power conversion device 21 (that is, the motor generator 12), etc. based on the information input from these various sensors. do. Sensors connected to the control device 30 include a rotation speed sensor 17 for detecting the rotation speed of the engine 11 (crankshaft 11a) (hereinafter also referred to as engine rotation speed; see also NE in FIG. 2); A vehicle speed sensor 18 that detects the speed (hereinafter also referred to as vehicle speed), an AP sensor (not shown) that detects the amount of operation of the accelerator pedal (hereinafter referred to as AP opening), and a brake sensor (not shown) that detects the amount of operation of the brake pedal. shown), a gear position sensor (not shown) that detects the gear position of the transmission TM, a battery sensor (not shown) that detects the output and temperature of the battery 20, and the like. The control device 30 also includes a main shaft rotation speed sensor for detecting the rotation speed of the input shaft 141 (hereinafter also referred to as main shaft rotation speed; see also NM in FIG. 2), the intake pressure of the engine 11 (intake pipe pressure ), an atmospheric pressure sensor (both not shown) for detecting atmospheric pressure, and the like may be connected.

For example, based on the running state of the vehicle 1, the control device 30 derives a target torque for the crank end torque (hereinafter also referred to as crank end required torque), which is the sum of the engine torque and the motor torque. As an example, the control device 30 determines the vehicle speed detected by the vehicle speed sensor 18, the AP opening detected by the AP sensor, and the required crank end torque required for running the vehicle 1 according to the vehicle speed and the AP opening. The required crank end torque is derived by referring to the map shown in FIG. Note that this map is stored in advance in the storage device of the control device 30, for example. Then, the control device 30 controls the engine torque and the motor torque so that the crank end torque becomes the crank end required torque.

Further, the control device 30 switches the operating state of the engine 11 between all-cylinder operation and non-cylinder operation based on the crank-end required torque. Specifically, the control device 30 causes the engine 11 to operate in a cylinder deactivation state when the crank end required torque is relatively small, and causes the engine 11 to operate in all cylinders when the crank end required torque increases to some extent. That is, the control device 30 improves the fuel efficiency of the vehicle 1 by deactivating the engine 11 when the required crank end torque is small, and by operating the engine 11 in all cylinders when the required crank end torque is large. To secure an appropriate crank end torque according to the running state of 1. A specific example of switching the operating state of the engine 11 by the control device 30 will be described later with reference to FIGS.

[Net specific fuel consumption (BSFC)]
The control device 30 also controls the engine 11 in consideration of a net fuel consumption rate (hereinafter referred to as "BSFC (Brake Specific Fuel Consumption)"). BSFC is obtained by dividing the fuel consumed in one cycle of the engine (fuel injection amount) by the output of the engine (net horsepower), and the smaller the value, the better the fuel efficiency.

The control device 30 controls engine torque based on BSFC. Specifically, the control device 30 refers to a BSFC characteristic model representing the BSFC characteristic of the vehicle 1 pre-stored in the storage device or the like of the control device 30, and controls the engine torque so that the BSFC becomes an optimum value. do.

[BSFC characteristics of the vehicle of the present embodiment]
Here, BSFC characteristics of the vehicle 1 will be described with reference to FIG. In FIG. 3, the vertical axis indicates BSFC [g/kWh], and the horizontal axis indicates engine torque [Nm].

As shown in FIG. 3, the cylinder deactivation BSFC, which is the BSFC of the vehicle 1 when the engine 11 is in cylinder deactivation, gradually decreases as the engine torque increases until the engine torque reaches the cylinder deactivation bottom torque. After reaching the cylinder deactivation bottom torque, it increases as the engine torque increases. That is, when the engine 11 is operated with cylinder deactivation, the value of BSFC is minimized when the engine torque becomes the cylinder deactivation bottom torque, and the fuel efficiency becomes the best. In other words, the cylinder deactivation bottom torque is the optimum fuel economy operating point of the engine 11 that is operated with the cylinder deactivated.

Further, although only a part is shown in FIG. 3, the all-cylinder BSFC, which is the BSFC of the vehicle 1 when the engine 11 is in full-cylinder operation, has the same tendency as the cylinder deactivation BSFC. Specifically, the all-cylinder BSFC gradually decreases as the engine torque increases until the engine torque reaches an all-cylinder bottom torque (not shown; however, all-cylinder bottom torque > non-cylinder bottom torque). After reaching the torque, it rises as the engine torque increases. That is, when the engine 11 is operated with all cylinders, when the engine torque becomes the all-cylinder bottom torque, the value of BSFC becomes the minimum, and the fuel efficiency becomes the best.

Note that the cylinder deactivation BSFC shown in FIG. 3 is an example of the cylinder deactivation net fuel consumption rate, and the all cylinders BSFC is an example of the all cylinders net fuel consumption rate. Further, since the all-cylinder switching bottom torque and the cylinder deactivation upper limit torque shown in FIG. 3 will be described later, description thereof will be omitted here.

[Cylinder deactivation bottom assist control]
The fuel consumption performance of the vehicle 1 can be improved by increasing the number of opportunities to operate the engine 11 so that the engine torque becomes the cylinder deactivation bottom torque (that is, at the optimum fuel efficiency operating point) during the cylinder deactivation operation of the engine 11 . On the other hand, when the engine 11 is operated with the cylinder deactivation bottom torque and it becomes impossible to secure an appropriate crank end torque according to the running state of the vehicle 1, hesitation (so-called sluggishness of the vehicle 1) occurs, and the driver ability can be reduced.

Therefore, the control device 30 increases the chances of operating the engine 11 with the cylinder deactivation bottom torque while securing an appropriate crank end torque according to the running state of the vehicle 1. to run.

In FIG. 4, the vertical axis indicates the engine torque [Nm], and the horizontal axis indicates the crank end torque (that is, the sum of the engine torque and the motor torque) [Nm].

As shown in FIG. 4, during the period until the engine torque reaches the cylinder deactivation bottom torque when the engine 11 is in cylinder deactivation operation (that is, the period in which the engine torque is less than the cylinder deactivation bottom torque), the control device 30: The engine 11 is controlled so as to secure the required crank end torque only by the engine torque. That is, during this period, the control device 30 increases the engine torque in accordance with the increase in the crank end required torque (see the one-dot chain line labeled 401 in FIG. 4). As a result, it is possible to obtain an optimum engine torque from the viewpoint of BSFC while ensuring an appropriate crank end torque according to the running state of the vehicle 1, thereby improving the fuel efficiency of the vehicle 1. FIG.

After that, when the crank end required torque reaches the cylinder deactivation bottom torque, the control device 30 executes cylinder deactivation bottom assist control. In the cylinder deactivation bottom assist control, the control device 30 increases the motor torque in accordance with the increase in the crank end required torque while maintaining the engine torque at the cylinder deactivation bottom torque (in FIG. ). As a result, the engine 11 can be operated at the fuel efficiency optimum operating point, and an appropriate crank end torque corresponding to the running state of the vehicle 1 can be ensured. Therefore, it is possible to improve the fuel consumption performance of the vehicle 1 while avoiding the occurrence of hesitation and the deterioration of drivability.

After that, when the crank-end required torque reaches the all-cylinder switching bottom torque while the cylinder deactivation bottom assist control is being executed, the control device 30 terminates the cylinder deactivation bottom assist control and changes the operating state of the engine 11. Switch to full cylinder operation. Here, as shown in FIG. 3, the all-cylinder switching bottom torque is the torque corresponding to the intersection of the curve representing the cylinder deactivation BSFC and the curve representing the all-cylinder BSFC. As a result, the operating state of the engine 11 can be switched from the cylinder deactivation operation to the all-cylinder operation at an appropriate timing from the BSFC point of view.

Further, when the operating state of the engine 11 is switched to all-cylinder operation, the control device 30 increases the engine torque in order to secure the required crank end torque only by the engine torque, and also increases the engine torque in accordance with the increase in the engine torque. Decrease the motor torque (see the dashed line labeled 403 in FIG. 4). As a result, in the running state of the vehicle 1 at that time, the optimum engine torque can be obtained from the viewpoint of BSFC. can be suppressed.

By the way, depending on the performance of the motor generator 12, the motor torque reaches the upper limit torque that the motor generator 12 can output (hereinafter also referred to as the motor upper limit torque) before the crank end required torque reaches the all-cylinder switching bottom torque. It is also possible. If the engine torque is maintained at the cylinder deactivation bottom torque even after the motor torque reaches the motor upper limit torque (that is, after the motor torque can no longer be increased), the engine torque will be reduced according to the running state of the vehicle 1. It may not be possible to secure an appropriate crank end torque.

Therefore, when the motor torque reaches the motor upper limit torque while the cylinder deactivation bottom assist control is being executed, the control device 30 ends the cylinder deactivation bottom assist control and changes the operating state of the engine 11 to full cylinder operation. You may make it switch. As a result, it is possible to ensure an appropriate crank end torque according to the running state of the vehicle 1, and to avoid the occurrence of hesitation and the deterioration of drivability.

Further, after switching to all-cylinder operation, when the engine torque, which has increased with the increase in crank end required torque, reaches the upper limit torque that the engine 11 can output (hereinafter also referred to as engine upper limit torque), the control device 30 , while maintaining the engine torque at the engine upper limit torque, power assist control may be executed to increase the motor torque in accordance with the increase in the crank end required torque (see the dashed line with reference numeral 404 in FIG. 4). . As a result, it is possible to ensure an appropriate crank end torque according to the running state of the vehicle 1 while appropriately operating the engine 11 at a torque equal to or lower than the engine upper limit torque.

Then, when the power assist control is being executed, when the motor torque that increases with the increase in the crank end required torque reaches the motor upper limit torque (i.e., the crank end torque is the sum of the engine upper limit torque and the motor upper limit torque), When a certain system upper torque limit is reached, the controller 30 may stop increasing the engine torque and motor torque and maintain the crank end torque at the system upper torque limit. This makes it possible to appropriately operate the engine 11 with a torque equal to or lower than the engine upper limit torque and the motor generator 12 with a torque equal to or lower than the motor upper limit torque.

As described above, the control device 30 that controls the vehicle 1 including the engine 11, the motor generator 12, and the drive wheels DW driven by the output of at least one of the engine 11 and the motor generator 12 controls the engine 11 When the crank end request torque reaches the cylinder deactivation bottom torque when the cylinder deactivation operation is being performed, the engine torque output from the engine 11 is maintained at the cylinder deactivation bottom torque, and according to the increase in the crank end request torque Cylinder deactivation bottom assist control for increasing the motor torque output from the motor generator 12 is executed. As a result, it is possible to increase the chances of operating the engine 11 with cylinder deactivation bottom torque while ensuring an appropriate crank end torque according to the running state of the vehicle 1 . Therefore, it is possible to improve the fuel efficiency of the vehicle 1 while suppressing deterioration of drivability.

On the other hand, if the motor assist is not performed when the engine 11 is in cylinder deactivation operation, it is necessary to secure the required crank end torque only by the engine torque. Therefore, if the crank end required torque becomes larger than the cylinder deactivation bottom torque, the engine torque must be increased accordingly, and the chances of operating the engine 11 at the cylinder deactivation bottom torque, which is the optimum fuel economy operating point, are reduced. become. In addition, in this way, in order to ensure crank end torque according to the running state of the vehicle 1, the engine torque must be reduced to the upper limit torque that the engine 11 can output in the cylinder deactivation operation state (hereinafter also referred to as the cylinder deactivation upper limit torque). ), it is necessary to switch the operating state of the engine 11 to full-cylinder operation. As shown in FIG. 3, the cylinder deactivation upper limit torque is generally smaller than the all-cylinder switching bottom torque. Accordingly, if this is done, the chances of operating the engine 11 with the cylinder deactivated also decrease. As described above, in this case, the fuel consumption performance becomes lower than that of the vehicle 1 of the present embodiment.

Next, another example of cylinder deactivation bottom assist control will be described with reference to FIG. FIG. 5 shows the temporal relationship among (a) vehicle speed, (b) operating state of engine 11, (c) various torques, and (d) AP opening.

In FIG. 5, the accelerator pedal is gradually depressed by the driver from time t10 when the vehicle 1 is running with the engine 11 in the cylinder deactivation state. Requested torque is gradually increasing. Since the crank end required torque is smaller than the cylinder deactivation bottom torque at the time before time t11, the control device 30 controls the engine 11 so as to ensure the crank end required torque only by the engine torque.

Then, at time t11 when the increased crank end request torque reaches the cylinder deactivation bottom torque, the control device 30 starts the cylinder deactivation bottom assist control, and maintains the engine torque at the cylinder deactivation bottom torque. Increase the motor torque as the torque increases.

After that, the crank end required torque further increases, and at time t12 when the crank end required torque reaches the all-cylinder switching bottom torque, the control device 30 ends the cylinder deactivation bottom assist control, and cranks the engine torque only. The engine torque is increased in order to secure the required end torque. Also, the control device 30 reduces the motor torque in accordance with the increase in the engine torque. Then, at time t13 immediately after time t12, the control device 30 switches the operating state of the engine 11 to all-cylinder operation.

Further, from time t14 after time t13, the driver has weakened the depression of the accelerator pedal, and along with this, the AP opening, vehicle speed, and crank end demand torque gradually decrease from time t14.

Then, at time t15 when the decreased crank-end required torque reaches the cylinder deactivation bottom torque, the control device 30 restarts cylinder deactivation bottom assist control. In the cylinder deactivation bottom assist control in this case, the control device 30 decreases the engine torque to achieve the cylinder deactivation bottom torque, and when the engine torque reaches the cylinder deactivation bottom torque, it is maintained as it is. Further, in the cylinder deactivation bottom assist control in this case, the control device 30 increases the motor torque in accordance with the decrease in the engine torque. As a result, when the operating state of the engine 11 is switched from full-cylinder operation to cylinder deactivation operation, it is possible to suppress the occurrence of a sudden change in crank end torque that may lead to deterioration of drivability. Then, at time t16 immediately after time t15, the control device 30 switches the operating state of the engine 11 to cylinder deactivation operation.

As described above, according to the control device 30 of the present embodiment, it is possible to increase the chances of operating the engine 11 with cylinder deactivation bottom torque while ensuring an appropriate crank end torque according to the running state of the vehicle 1. Therefore, it is possible to improve the fuel efficiency of the vehicle 1 while suppressing deterioration of drivability.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and can be modified, improved, and the like as appropriate.

For example, in the embodiment described above, an example in which the engine 11 and the motor generator 12 are connected via the crankshaft 11a has been described, but the present invention is not limited to this. For example, the motor generator 12 may be coupled to a drive shaft that rotates integrally with the drive wheels DW.

In addition, at least the following matters are described in this specification. In addition, although the parenthesis shows the components corresponding to the above-described embodiment, the present invention is not limited to this.

(1) A vehicle (vehicle 1) including an internal combustion engine (engine 11), an electric motor (motor generator 12), and driving wheels (driving wheels DW) driven by the output of at least one of the internal combustion engine and the electric motor. A vehicle control device (control device 30) that controls
The internal combustion engine is configured to be switchable between full-cylinder operation in which all cylinders are operated and cylinder-deactivated operation in which some cylinders are deactivated,
The vehicle control device includes:
Based on a target torque for a crank end torque, which is torque at the shaft end of the crankshaft of the power plant torque output from the power plant composed of the internal combustion engine and the electric motor, the operating state of the internal combustion engine is changed to full-cylinder operation and It is possible to switch between cylinder deactivation operation and control the output of the internal combustion engine based on the net fuel consumption rate,
When the internal combustion engine is operating with the cylinder not operating, the target torque is set so that the value of the cylinder deactivating net fuel consumption rate, which is the net fuel consumption rate when the internal combustion engine is operating with the cylinder not operating, is the minimum. When the cylinder bottom torque is reached, cylinder deactivation bottom assist increases the motor torque output from the electric motor in accordance with the increase in the target torque while maintaining the engine torque output from the internal combustion engine at the cylinder deactivation bottom torque. to carry out control,
Vehicle controller.

According to (1), it is possible to increase the chances of operating the internal combustion engine with cylinder deactivation bottom torque while ensuring an appropriate crank end torque according to the running state of the vehicle, thereby suppressing deterioration of drivability. , it is possible to improve the fuel efficiency of the vehicle.

(2) The vehicle control device according to (1),
When the target torque reaches an all-cylinder switching bottom torque that is larger than the cylinder deactivation bottom torque while the cylinder deactivation bottom assist control is being executed, the cylinder deactivation bottom assist control is terminated, and the internal combustion engine switching the operating state of to the all-cylinder operation,
The all-cylinder switching bottom torque is obtained by combining a curve representing the cylinder deactivation net fuel consumption rate and a curve representing the all-cylinder net fuel consumption rate, which is the net fuel consumption rate when the internal combustion engine is operating in all cylinders. is the torque corresponding to the intersection point,
Vehicle controller.

According to (2), the operating state of the internal combustion engine can be switched from cylinder deactivation operation to all-cylinder operation at an appropriate timing from the viewpoint of the net fuel consumption rate.

(3) The vehicle control device according to (1),
When the motor torque reaches the upper limit torque that the electric motor can output while the cylinder deactivation bottom assist control is being executed, the cylinder deactivation bottom assist control is terminated, and the operating state of the internal combustion engine is changed to the switch to full-cylinder operation,
Vehicle controller.

According to (3), it is possible to ensure an appropriate crank end torque according to the running state of the vehicle, and to avoid the occurrence of hesitation and the deterioration of drivability.

1 vehicle 11 engine (internal combustion engine)
12 motor generator (electric motor)
30 control device (vehicle control device)
DW drive wheel

Claims (3)

A vehicle control device for controlling a vehicle including an internal combustion engine, an electric motor, and driving wheels driven by at least one output of the internal combustion engine and the electric motor,
The internal combustion engine is configured to be switchable between full-cylinder operation in which all cylinders are operated and cylinder-deactivated operation in which some cylinders are deactivated,
The vehicle control device includes:
Based on a target torque for a crank end torque, which is torque at the shaft end of the crankshaft of the power plant torque output from the power plant composed of the internal combustion engine and the electric motor, the operating state of the internal combustion engine is changed to full-cylinder operation and It is possible to switch between cylinder deactivation operation and control the output of the internal combustion engine based on the net fuel consumption rate,
When the internal combustion engine is operated with the cylinder deactivated, the target torque is the value of the cylinder deactivated net fuel consumption rate, which is the net fuel consumption rate when the internal combustion engine is operated with the cylinder deactivated. When the cylinder bottom torque is reached, cylinder deactivation bottom assist increases the motor torque output from the electric motor in accordance with the increase in the target torque while maintaining the engine torque output from the internal combustion engine at the cylinder deactivation bottom torque. perform control,
Vehicle controller. The vehicle control device according to claim 1,
When the target torque reaches an all-cylinder switching bottom torque that is larger than the cylinder deactivation bottom torque while the cylinder deactivation bottom assist control is being executed, the cylinder deactivation bottom assist control is terminated, and the internal combustion engine switching the operating state of to the all-cylinder operation,
The all-cylinder switching bottom torque is obtained by combining a curve representing the cylinder deactivation net fuel consumption rate and a curve representing the all-cylinder net fuel consumption rate, which is the net fuel consumption rate when the internal combustion engine is operating in all cylinders. is the torque corresponding to the intersection point,
Vehicle controller. The vehicle control device according to claim 1,
When the motor torque reaches the upper limit torque that the electric motor can output while the cylinder deactivation bottom assist control is being executed, the cylinder deactivation bottom assist control is terminated, and the operating state of the internal combustion engine is changed to the switch to full-cylinder operation,
Vehicle controller.

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